Enhanced Heat Transfer Technology And Numerical Simulation Of Low Temperature Waste Heat Recycling

Our country's energy per capita ownership is only the world average level in the world behind the 19.4%level. In the international advanced level of the industry, its energy utilization rate averaged of up to 60%, our industrial energy utilization rate averaged only 33%, this and in low-temperature waste heat utilization rate is low, severe waste closely related. Low temperature waste heat recovery technology should be enhanced urgently. This article mainly studied the flue gas recovery of waste heat of the pipe strengthening technology, based on thermodynamics, heat transfer and fluid mechanics analysis method, using CFD simulation, combining the pipe geometric structure, concrete research wrong platoon flue gas trans-monounsaturated row over under gravity field, the velocity field and temperature field in the convective heat transfer characteristics, the author puts forward some methods of improvement.In the tube tail drafting deteriorating characteristics of heat transfer effect and put forward two solutions:first:increased reflow temperature; Second:to promote fluid mixing speed, reducing back to flow. Based on this design was obtained relatively concave and convex shape of two new outside the pipe. On the traditional lightpipes numerical simulation results with the subsection power times experimental comparison, relational that average surface heat transfer coefficient is very good, and verifies the consistent numerical simulation adaptability. Additionally, through and traditional heat exchange tube heat transfer and resistance performance comparison shows, two new types of the pipe thermal improve is 4.8 per 1,000,17.6 per 1,000; The average drag coefficient reducing 6.74%, 4.94%. Two kinds of the pipe to apply the dislocation structure, analyzes their heat resistance characteristic, and fitting out relational.Aiming at the wrong row structural pressure loss of big disadvantage, this paper introduces a design with poor orders of magnitude rib column the pipe. For the heat exchange tube analysis, in the rib column and base tube profile formed between 3d wrong row structure of rib column diameter and the tube diameter difference 1 orders of magnitude characteristics, guarantee in resistance increased little at the same time, in the heat transfer surface to form strong secondary turbulence, improve the heat transfer effect. Carry on the 3-d numerical simulation, with poor orders of magnitude profile structure of fault row in X direction section velocity component was improved obviously, Z direction velocity component dramatically reduce that this the pipe in improving thermal, reduce sulphuric acid, improve the pipe wear degree is feasible. From energy use Angle heat-exchange capability evaluation, namely waste heat and pressure drop by energy where, the greater the energy recovery ratio of the better, so this index studied sent orders of magnitude wrong dislocation structure of heat transfer characteristics, with poor orders of magnitude profile structure of fault row section pressure drop increase lower speed change heat gain speed, Rib column height and gradient design should guarantee the rib column section and the corresponding matrix tube profile of the distance in between 0～22.5mm, now has better heat exchange performance. In addition, CFD model of flow field and temperature field calculation results to further optimize the pipe design provides the theoretical calculation.